Question

[CoF₆]³⁻ is a coordination complex ion.

How many unpaired electrons are there in the complex?

Answer 1

There are 4 unpaired electrons in the [CoF₆]³⁻ complex ion because cobalt is in the +3 oxidation state (Co³⁺), with an electron configuration of 3d⁶, and fluorine (F⁻) is a weak-field ligand that leads to a high-spin configuration, resulting in four electrons occupying the 3d orbitals individually.